Northern Ireland

Ligoniel Dam: Warning issued as blue green algae identified at Belfast heritage dam site

Ligoniel Improvement Association says it has been left in limbo

Blue green algae has taken over Ligoneil Dam in North Belfast
Blue green algae has taken over Ligoniel Dam in north Belfast

Concerns have been raised about blue-green algae at a heritage site in north Belfast.

The potentially dangerous algae was first spotted at Ligoniel Dam last week.

During a bloom, the water becomes less clear and may look green, blue-green or greenish-brown

The algae appears as a result of factors including increased temperatures and pollution and when it blooms it can produce harmful toxins.

Warning signs have been erected urging people and their pets to avoid the water.

Maria Morgan, CEO of Ligoniel Improvement Association, said that this is the first time the blooms have appeared at the Ligoniel site.

However, she was critical of the Department of Agriculture, Environment and Rural Affairs (DAERA) saying that the group had been left in limbo since the discovery.

Warning signs have been erected at the site
Warning signs have been erected at the site

“When we received the initial call from from DAERA confirming the presence of the algae we asked for advice and they directed us to their website,” she explained.

“Despite numerous calls and emails for information there has been no further engagement or support on the matter.

“In terms of the waterways it’s a limited area when it comes down to where the algae could have come from yet we don’t have any clarification as to how it got there in the first place. We have received zero support and we are calling for active engagement to get this addressed.

“People are really concerned. This is an open body of water that’s home to a variety of birds and wildlife and we have had to reach out to the RSPB to come along to see if they can help with that.

“We are also a small charity who host community activities over the summer holidays but at the moment we have no answers for when or if they will be able to take place. We have been left in limbo.”



Blue-green algae also known as cyanobacteria, has been detected in multiple locations across Northern Ireland including some lakes and rivers.

Belfast City Council has warned people and their pet dogs to avoid contact with affected water.

A spokesperson said: ““Belfast City Council received notification from DAERA that ‘potentially toxic blue green algae’ had been identified at the Wolfhill Dams at Ligoniel.

“We contacted the management associations for the upper and middle dams to advise them to erect signage.

“Belfast City Council has also erected signage on land surrounding the lower dam and Boodles Dam as a precaution.”

Belfast City Council urged people visiting the site to take care
Belfast City Council urged people visiting the site to take care

DAERA did not directly respond to the criticism instead signposting information available through the links below.

A list of the confirmed locations including that at Ligoniel can be found here

Advice from DAERA can be found here